Insecticide baits are made by:

Insecticide baits are specifically designed to attract insects, which is a fundamental part of their efficacy. By mixing insecticide with a substance that is appealing to insects, such as sugars or fats, the bait entices the target pests to consume it. This method is particularly effective because it allows the pesticide to be delivered directly into the pest's system, often resulting in a more efficient kill compared to other application methods.

This approach also takes advantage of the natural behaviors of insects, as they are drawn to the attractant and are more likely to ingest the insecticide when it is presented in a palatable form. This not only helps in controlling the pest population but can also minimize the impact on non-target species.

The other methods mentioned do not perform this dual function of attraction and killing, which is why they do not match the definition of insecticide baits. Mixing insecticide with water primarily creates a spray, coating a surface with insecticide typically involves a pesticide being utilized as a surface treatment, and formulating into dust implies application in a form that may not attract the pest effectively.